# A Public-Key Cryptosystem Based on the Word Problem

Conference paper

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## Abstract

The undecidable word problem for groups and semigroups is investigated as a basis for a public-key cryptosystem. A specific approach is discussed along with the results of an experimental implementation. This approach does not give a provably secure or practical system, but shows the type of cryptosystem that could be constructed around the word problem. This cryptosystem is randomized, with infinitely many ciphertexts corresponding to each plaintext.

## Keywords

Word Problem Quotient Group Special Word Extra Relator Undecidable Problem Download
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## Copyright information

© Springer-Verlag Berlin Heidelberg 1985